chore: import upstream snapshot with attribution

basics/base_augmentation.py

@@ -0,0 +1,28 @@
+from utils.hparams import hparams
+
+
+class BaseAugmentation:
+    """
+    Base class for data augmentation.
+    All methods of this class should be thread-safe.
+    1. *process_item*:
+        Apply augmentation to one piece of data.
+    """
+    def __init__(self, data_dirs: list, augmentation_args: dict):
+        self.raw_data_dirs = data_dirs
+        self.augmentation_args = augmentation_args
+        self.timestep = hparams['hop_size'] / hparams['audio_sample_rate']
+
+    def process_item(self, item: dict, **kwargs) -> dict:
+        raise NotImplementedError()
+
+
+def require_same_keys(func):
+    def run(*args, **kwargs):
+        item: dict = args[1]
+        res: dict = func(*args, **kwargs)
+        assert set(item.keys()) == set(res.keys()), 'Item keys mismatch after augmentation.\n' \
+                                                    f'Before: {sorted(item.keys())}\n' \
+                                                    f'After: {sorted(res.keys())}'
+        return res
+    return run